New Zealand First leader Winston Peters says he hopes the country's ban on conversion therapy is overturned.

In a wide-ranging interview with Family First, Peters also said abortion could, depending on its timing, shade into "murder or assassination".

But National's leader Christopher Luxon has quickly shot down any suggestion the debates might be reopened under his role as Prime Minister.

Speaking to Family First's Bob McCoskrie, Peters said NZ First would have fought the conversion-practices law if it had been in Parliament when it passed in 2022.

Asked whether there should be moves to overturn or relitigate the law, Peters replied on Thursday: "I sure hope so."

But he stopped short of making repeal an election policy.

On abortion, Peters said "the facts" were worth revisting and repeated his view that life begins at conception.

"At its worst, and it's a matter of timing, but it shades into a thing called murder," Peters said.

"It shades into a thing called murder or assassination - get any name you like."

Speaking to reporters in Kapiti, Luxon said the laws were settled and he would not be changing them.

"I said in 2023 I would not be changing them as Prime Minister, and I've met that commitment, and I'll continue to meet that commitment," he said.

"There will be no changes under me as Prime Minister."

Luxon also shot down Peters' hopes for reversing the conversion therapy ban: "No, we're not overturning that at all. That's not changing whatsoever."

Asked for his response, Labour campaign chairperson Kieran McAnulty said Peters was just making outrageous comments as a "distraction tactic".

"Winston Peters makes all these claims with no intention of following it up.”

McAnulty said Luxon and National campaign chair Simeon Brown would probably be pleased by Peters' remarks, given their personal views on abortion.

But he said Labour was focused on the cost of living.

"No one so far in this campaign... has come up to me and said we need to reverse conversion therapy and we need to change the laws around abortion.

"Almost everybody that's come up to me has talked about the cost of living."